| /******************************************************************************* |
| * Copyright (c) 2008 Oracle. |
| * All rights reserved. This program and the accompanying materials are |
| * made available under the terms of the Eclipse Public License v1.0 which |
| * accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Oracle - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.jpt.core.internal.resource; |
| |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import org.eclipse.core.runtime.CoreException; |
| import org.eclipse.core.runtime.IConfigurationElement; |
| import org.eclipse.core.runtime.IExtension; |
| import org.eclipse.core.runtime.IExtensionPoint; |
| import org.eclipse.core.runtime.Platform; |
| import org.eclipse.jpt.core.JptCorePlugin; |
| import org.eclipse.jpt.core.resource.JpaResourceModelProviderFactory; |
| import org.eclipse.jpt.utility.internal.CollectionTools; |
| import org.eclipse.jpt.utility.internal.iterators.CompositeIterator; |
| import org.eclipse.jpt.utility.internal.iterators.TransformationIterator; |
| |
| /** |
| * Singleton registry for storing all the registered JPA resource model provider |
| * elements and instantiating JPA resource model provider factories from them. |
| */ |
| public class JpaResourceModelProviderRegistry |
| { |
| // singleton |
| private static final JpaResourceModelProviderRegistry INSTANCE = new JpaResourceModelProviderRegistry(); |
| |
| private static final String EXTENSION_ID = "resourceModelProviders"; //$NON-NLS-1$ |
| private static final String EL_MODEL_PROVIDER = "modelProvider"; //$NON-NLS-1$ |
| private static final String AT_FILE_CONTENT_TYPE = "fileContentType"; //$NON-NLS-1$ |
| private static final String AT_FACTORY_CLASS = "factoryClass"; //$NON-NLS-1$ |
| |
| |
| /** |
| * Return the singleton. |
| */ |
| public static JpaResourceModelProviderRegistry instance() { |
| return INSTANCE; |
| } |
| |
| |
| private final HashMap<String, IConfigurationElement> configElements; |
| |
| |
| public JpaResourceModelProviderRegistry() { |
| super(); |
| this.configElements = this.buildConfigElements(); |
| } |
| |
| |
| private HashMap<String, IConfigurationElement> buildConfigElements() { |
| HashMap<String, IConfigurationElement> configElements = new HashMap<String, IConfigurationElement>(); |
| for (Iterator<IConfigurationElement> stream = this.configElements(); stream.hasNext(); ) { |
| this.addConfigElementTo(stream.next(), configElements); |
| } |
| return configElements; |
| } |
| |
| /** |
| * Return the configuration elements from the Eclipse platform extension |
| * registry. |
| */ |
| private Iterator<IConfigurationElement> configElements() { |
| return new CompositeIterator<IConfigurationElement>( |
| new TransformationIterator<IExtension, Iterator<IConfigurationElement>>(this.extensions()) { |
| @Override |
| protected Iterator<IConfigurationElement> transform(IExtension extension) { |
| return CollectionTools.iterator(extension.getConfigurationElements()); |
| } |
| } |
| ); |
| } |
| |
| private Iterator<IExtension> extensions() { |
| return CollectionTools.iterator(this.extensionPoint().getExtensions()); |
| } |
| |
| private IExtensionPoint extensionPoint() { |
| return Platform.getExtensionRegistry().getExtensionPoint(JptCorePlugin.PLUGIN_ID, EXTENSION_ID); |
| } |
| |
| private void addConfigElementTo(IConfigurationElement configElement, HashMap<String, IConfigurationElement> configElements) { |
| if ( ! configElement.getName().equals(EL_MODEL_PROVIDER)) { |
| return; |
| } |
| if ( ! this.configElementIsValid(configElement)) { |
| return; |
| } |
| |
| String fileContentType = configElement.getAttribute(AT_FILE_CONTENT_TYPE); |
| IConfigurationElement prev = configElements.get(fileContentType); |
| if (prev == null) { |
| configElements.put(fileContentType, configElement); |
| } else { |
| this.logDuplicateFileContentType(prev, configElement); |
| } |
| } |
| |
| /** |
| * check *all* attributes before returning |
| */ |
| private boolean configElementIsValid(IConfigurationElement configElement) { |
| boolean valid = true; |
| if (configElement.getAttribute(AT_FILE_CONTENT_TYPE) == null) { |
| this.logMissingAttribute(configElement, AT_FILE_CONTENT_TYPE); |
| valid = false; |
| } |
| if (configElement.getAttribute(AT_FACTORY_CLASS) == null) { |
| logMissingAttribute(configElement, AT_FACTORY_CLASS); |
| valid = false; |
| } |
| return valid; |
| } |
| |
| |
| // **************** public methods ***************************************** |
| |
| /** |
| * Return a new JPA Resource Model Provider Factory for the specified file |
| * content type. |
| * NB: Invoking this method may activate the plug-in. |
| */ |
| public JpaResourceModelProviderFactory getResourceModelProviderFactory(String fileContentType) { |
| IConfigurationElement configElement = configElements.get(fileContentType); |
| if (configElement == null) { |
| throw new IllegalArgumentException(fileContentType); |
| } |
| JpaResourceModelProviderFactory factory; |
| try { |
| factory = (JpaResourceModelProviderFactory) configElement.createExecutableExtension(AT_FACTORY_CLASS); |
| } catch (CoreException ex) { |
| this.logFailedInstantiation(configElement, ex); |
| throw new IllegalArgumentException(fileContentType); |
| } |
| return factory; |
| } |
| |
| // **************** errors ************************************************* |
| |
| // TODO externalize strings |
| private void logMissingAttribute(IConfigurationElement configElement, String attributeName) { |
| String message = |
| "An extension element \"" |
| + configElement.getName() |
| + "\" in plugin \"" |
| + configElement.getContributor().getName() |
| + "\" is missing a required attribute \"" |
| + attributeName |
| + "\"."; |
| JptCorePlugin.log(message); |
| } |
| |
| // TODO externalize strings |
| private void logDuplicateFileContentType(IConfigurationElement prevConfigElement, IConfigurationElement newConfigElement) { |
| String message = |
| "The plugins \"" |
| + prevConfigElement.getContributor().getName() |
| + "\" and \"" |
| + newConfigElement.getContributor().getName() |
| + "\" have registered a duplicate attribute \"" |
| + AT_FILE_CONTENT_TYPE |
| + "\" " |
| + "for the extension element \"" |
| + EL_MODEL_PROVIDER |
| + "\"."; |
| JptCorePlugin.log(message); |
| } |
| |
| // TODO externalize strings |
| private void logFailedInstantiation(IConfigurationElement configElement, CoreException ex) { |
| String message = |
| "Could not instantiate the class \"" |
| + configElement.getAttribute(AT_FACTORY_CLASS) |
| + "\" for the extension element \"" |
| + configElement.getName() |
| + "\" in the plugin \"" |
| + configElement.getContributor().getName() |
| + "\"."; |
| JptCorePlugin.log(ex); |
| JptCorePlugin.log(message); |
| } |
| } |